We develop an American website. From the beginning of December it has been visited by doubtful users (perhaps, bots). We had been initially thinking that it was a referral spam, but there were more and more users, and American IP were appeared. They move to the site using a direct link (whereas referral spammers goes from a specific resource promoted). Further, they started to increase stay on site time. They currently spend 50 minutes there and periodically surf the pages. There are a lot of content on our website, but it is not able to be parsed with such speed, so it is not a parsing. We have tried to ban their IP, but there is no any result. They continue to visit our site using other IP. The question is whether it is possible to obtain a filter for those visits, because Google may think that we cheat behavioral factors. It is clear there is a disavow links tool that allow to refuse the links. How can we let Google know that these are not our traffic cheats and we cannot limit them? What is more, it goes gradually. Those who do it are increasing every day stays on the site for a minute or two and look through more pages. Now this traffic is already 1/5 of all traffic on our website. It grows every day.